Two weeks before terrorists flew airliners into the World Trade Center towers and the Pentagon, an odd e-mail from overseas popped into Dan Seufert's computer at Daniel Webster College. The sender wanted to visit the Nashua, N.H., school, but needed a formal invitation to get a visa to enter the United States.

"The official invitation means that your Daniel Webster College is inviting us officially," the awkward e-mail read. "I hope to get the visa easily to meet your goodself."

In hindsight, Mr. Seufert, director of external relations, says he now wonders "if the writer really was a woman from India." Because Daniel Webster College trains pilots, and some of the Sept. 11 terrorists had flight training at American schools, Seufert is nagged by questions: Might the e-mail writer have been a terrorist, or someone seeking a document to sell on the black market for use in acquiring a US student visa?

In the halls of Congress, some are questioning whether US higher education - long known for opening doors to the best and brightest of all nations - is a bit too open. Others are concerned that if the country tightens lab research and student-visa requirements, it will shoot itself in the foot and squelch the cultural and economic dynamo that US higher education has become.

"Our science and engineering fields depend heavily on foreign students and foreign exchange programs," says Lawrence Faulkner, president of the University of Texas at Austin. "If we were to close down this channel in a heavy-handed way, it would be to [the country's] detriment."

Perhaps the most intense federal focus is on student visas. Last Wednesday, Immigration and Naturalization Service agents in San Diego arrested 10 young people from the Middle East who were not properly enrolled in college or had overstayed their visas. Officials said it was the first step in a growing national crackdown on student visas.

That may be just the beginning. Congress is also weighing proposed moratoriums - lasting up to nine months - on granting student visas, a move that could throw a monkey wrench into university research efforts, in which foreign students play a major role nationwide.

The backbone of graduate research

"We oppose restrictions, limits on student visas of any kind," says Glen Gaulton, vice dean for research and research training at the University of Pennsylvania. "The quality of research would suffer. Yes, we could bring in more domestic technicians. But our research would slow down. They're just not as highly motivated as the foreign students."

Students from abroad have become the backbone of graduate research in American higher education. In the post-Sputnik era of the 1960s, Dr. Gaulton says, the best American universities recognized the global supply of talent and began to open their doors to foreign graduate students. Now, US higher education has become reliant upon them, he says.

A record 547,867 international undergraduate and graduate students were enrolled at US campuses last year, a 6.4 percent rise over the previous year and the largest jump since 1980, reports the Institute of International Education.

But more "help wanted" signs are springing up.

"You've got a tremendous shortage already of research assistants at most top labs," Gaulton says. "We cannot attract enough domestic graduate students. We've got to get them overseas."

Mutlu Ozdogan is a Turkish graduate research assistant in Boston University's geology department. He is working on groundbreaking satellite remote-sensing technology, and has a visa that should be good for several more years.

Even so, he worries that it may be hard for him to reenter the US after an upcoming research trip to the United Arab Emirates. He is not reassured by the crackdown in San Diego.

"There's no place in the [visa] application about my research," he says. "So I'm trying to plan ahead to bring extra documents with me. I will get a letter from the chair of my department, to show I am not a terrorist - just a researcher."

Research isn't the only contribution by foreign students. They shell out about $11 billion annually in the US, for one thing. But their main value to education is not as a "cash cow," notes David Ward, president of the American Council on Education, a lobby group for colleges and universities in Washington.

From diversity to diplomacy

Foreign students make up just 3.9 percent of 14 million college students nationwide. But their presence gives many campuses a polyglot, global atmosphere that schools value and tout in marketing materials.

"Having undergraduates exposed to these students is a very important part of their education," Dr. Ward says. "It provides a junior year abroad without having to go there. Many undergrads recognize it's kind of neat to have someone from Sweden teaching them."

Conversely, for the likes of Mr. Ozdogan and thousands of foreign students, learning about American freedoms and culture is a big part of the experience - and they often return home with a positive attitude about the US. That alone is "a huge foreign-policy asset," says Victor Johnson, associate executive director for public policy at the National Association of International Educators, a Washington lobby group.

"Those people who go back home are forces for modernization and openness in their own countries," he says. "Why would we want to stop educating these people? No serious person could think it would not be beneficial to educate the next generation of world leaders in the US."

But the question remains: How to stop future Hani Hanjours?

Hanjour was one of the hijackers of the airliner that struck the Pentagon - the only one of the 19 terrorists in the Sept. 11 attacks who was visiting the US on a student visa. Yet nobody seems to have noticed when he did not report as expected to a language school in California.

"Today there is little scrutiny given to those who claim to be foreign students seeking to study in the United States," said Sen. Dianne Feinstein (D) of California in a statement in October. "The foreign-student visa program is one of the most unregulated and exploited visa categories."

Among the student influx last year were 3,761 from Libya, Sudan, North Korea, Iran, Iraq, Syria, and Cuba - seven nations the US State Department calls sponsors of terrorism. To be sure, many such students came to the US college system after fleeing their homes and living in exile, Mr. Johnson points out.

Still, Senator Feinstein wonders about the 16,000 students from those terror-sponsoring nations who passed through American colleges in the past decade. She asked immigration officials this fall where these people are today. They didn't know.

So while an embarrassed INS cracks down on foreign students on its own, Feinstein and Senate colleagues are also pushing legislation to beef up scrutiny of visa applicants and track foreign students once they arrive. It would authorize $32 million for the INS to build a database to track foreign students. The schools would also have to let the government know if students who are expected to show up do not do so within 30 days.

Still, Feinstein has backed off the most controversial part of her plan: a six-month moratorium on student visas. She is satisfied with promises from higher-education groups that their schools will cooperate with the INS until the tracking system is running.

A possible pause in granting visas

That big shift has higher-education lobbyists and faculty researchers breathing a huge sigh of relief. But should they be?

Several bills still pending in the House of Representatives would adopt a nine-month moratorium on student visas, along with other tough measures. State Department officials told the Monitor they are not certain that the milder, compromise Senate legislation will trump House bills that still call for a moratorium.

In addition, passage of the Patriot Act in October has made it easier for federal officials to require, and for colleges to hand over, previously restricted information and documents about students.

So far, at least 200 universities and colleges have responded to requests for such information by federal officials since Sept. 11, according to the American Association of Collegiate Registrars and Admissions Officers.

The Patriot Act also holds added potential to restrict university lab research involving "select agents" such as anthrax and ebola. About 250 university labs are currently registered to conduct such research. Federal inspectors from the Department of Health and Human Services have begun to check into those labs.

The impact of closer scrutiny - even if not yet widely applied - is unnerving for many foreign graduate students.

Jiaer Wu, a graduate student at the University of California at Berkeley, expects to get his PhD within a year. He's forgoing a long-awaited vacation back to China for fear of not being able to get back into the US. So are his friends. It's a shame, he says, because foreign students tend to be boosters for America abroad.

"I think most foreign students are very young and it's a very important time for them to check out America," Mr. Wu says. "I personally had a very good feeling about America. But America seems different to me now. People should realize, not everybody foreign is a terrorist, just a handful."

US's science development may be hit

Farouk El-Baz is director of the Center for Remote Sensing at Boston University, which ranks fifth among universities with the most foreign students (about 4,400 out of 28,300).

He says student researchers like Ozdogan are conducting vital, cutting-edge research using satellite-data analysis of groundwater. Most of the 60 research assistants are foreign, he says.

Restrictions on visas would be "not just a matter of holding students back - it's really holding America's science and technology development back," Mr. El-Baz says. "There's no reason to do such a thing."

America still 'the place we must go'

Some worry that tougher visa requirements and a longer wait would keep foreign students from trying to study in the US, but Wu does not think that is the case.

"America is the place we must go," he says, "even if it takes a long time to get there."

Some students, however, may never get a chance. With more federal oversight, school officials have an incentive to tighten their reviews of foreign students. Back at Daniel Webster College, Seufert decided to err on the side of caution and deny the request for a formal invitation.

"It didn't feel right," he says.

E-mail claytonm@csps.com.

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